Transmitting units are known through, for instance, WO 97/35208 and U.S. Pat. No. 5,917,425. Although there are known transmitting units and they can function well for some applications, there are certain uses and circumstances where it would be an advance in the art to provide improved transmitting units.
U.S. Pat. No. 6,276,814 concerns a lighting appliance having a movement sensor. Such an appliance might be useful in new applications, if suitable improvements and alterations could be made to make it better related to specific conditions.
The present invention therefore relates to a transmitting unit having a transmitter for transmitting signals of coded information about a position close to the unit in a space which may be substantially unreachable by a satellite-based navigating system so as to provide a receiver arranged on a moving object, such as a person, present in the space with this position information for determining the position of this object. Thus, the transmitter provides position information even in spaces unreachable by a satellite based navigation system but can with advantage also be used in spaces reachable by a satellite-based navigating system.
The object in question may be of any type able to move, such as a living being or even any type of robot, vehicle or the like. However, the case of such an object in the form of a human being, i.e. a person, will hereinafter be discussed for simplifying the explanation of the invention.
The space may be a room in a building or any other space substantially unreachable by a satellite-based navigating system, such as a space outdoors close to a building, in a mountain region, in any type of cave or tunnel or the like. Although not necessary, the person may also be provided with a transmitter sending position information further to any type of central unit registering and processing this information, possibly together with position information about other persons and/or about the environment in which the person is moving. In the case of a space in the form of a room in a building the position information may consist of information about in which building, in which floor and in which room the person is present.
According to the invention, a plurality of such transmitting units may be arranged in different spaces located close to each other, such as in different rooms in a building, or even in the same room thereof. It is not necessary that in such a case all the transmitting units are arranged in a space substantially unreachable by a satellite-based navigating system, but some of them may be arranged in a space well reachable by such a system.
Such an inventive transmitting unit may be arranged for assigning position information to a person for many different purposes, and some of them may be mentioned here as a not exhausting listing of examples. Transmitting units of this type may be used for assigning fire fighters position information for by a communication and/or managing centre assist the fire fighters to find their way and/or to make it possible to find a fire fighter needing help. Another possibility is to have such transmitting units in different rooms of museums and provide the visitors with a receiver for making it possible to provide each visitor with information associated with the instantaneous location of the visitor.
However, for the purpose of illuminating but not in any way restricting the present invention, the application of such a transmitting unit to a military exercise of combat in an area having at least any space substantially unreachable by a satellite-based navigating system will hereinafter be described. In the case of a military exercise of combat in buildings at least one transmitting unit of this type may be arranged in each room of a building in which a soldier may be present. The transmitters of the transmitting units known are then continuously transmitting signals of coded position information, such as infrared light pulses, out into the room. When a soldier is located in the room the receiver on the soldier will receive these pulses and after some processing transmit them further to a central unit for governing the military exercise, so that this central unit always knows where the different soldiers participating in the exercise are located. This means a possibility to make the military exercise realistic in the sense that the influence of different weapons upon the state of the soldiers may be the same as in a real combat. When for instances a hand-grenade is thrown through a window and into a room in a building the persons located in the room may be considered to be dead or hurt. Similar conclusions may be drawn when a building is considered to be partly or totally destroyed by a grenade or if any type of gas creating any type of condition of a soldier is supplied to any particular room. Such a military exercise may of course also take place partly in open areas, such as between buildings, in ditches and the like.